The trust algorithm
by Trbl
Summary: AU from the guys' return from the Arctic at the beginning of Season 3. Their new neighbor may be a vampire. Who you gonna call? Peter Vincent, of course. Shenny, and I'm not a Leonard fan.
1. Chapter 1

Disclaimer: If you recognize it, it almost certainly does not belong to me. Although, I'd take Sheldon, or Peter Vincent anytime

Please note that this takes place at the beginning of Season 3 and is AU. Very, very AU. The guys are just returning home from the Arctic, after doing Sheldon's monopole experiments. That much you may recognize. Anything after that, I make no promises.

Also note that there will be Adult Themes, including blood. If such things disturb you… better give this a miss.

Spoilers for "Fright Night"

Thanks to SpaceAnJL for enabling, letting me bounce ideas off of her and for help in a thousand other ways. All mistakes are entirely my own.

Part 1

Leonard Hofstadter, Howard Wolowitz and Raj Koothrappali trudged into the apartment building at 4311 Los Robles after a long cold time at the Arctic. They were complaining about the extreme conditions, how dreadful it had been and how glad they were to be home.

The final member of their little band of scientists was confused by them "I don't know what expedition y'all were on, but I thought that it was a hoot and a half." Sheldon Cooper's Texas twang, usually buried, came out just a little.

The guys gave him a disbelieving look, and started on their way to the stairs when a curvy blonde popped her head out of apartment 1A. "Oh, I thought you were the delivery guys." She was about 5 foot 9, with straight, long blond hair, dark brown eyes, and wearing a body hugging dress. Only Sheldon seemed unmoved by her attractiveness.

"Hi," said Leonard awkwardly.

"Hi." She said back.

"Hi," Leonard repeated.

"Oh, no, not again." Sheldon said with a moan.

"I'm Vivienne," the woman said after staring in bemusement at the guys.

The others scrambled to introduce themselves as Sheldon finished his trek up the stairs. He deposited the load that he was carrying in his apartment, noting that Penny must have aired it as he had requested.

Knowing that assumptions were to be avoided where Penny was concerned, and also knowing that Leonard would be distracted by Vivienne for a few moments, Sheldon decided to inform Penny of their return, and seek reassurance that she had followed his instructions.

Knock, knock, knock, "Penny," he began his ritual knock on their neighbor's door.

Knock, knock, knock, "Penny,"

Knock, knock, knock, "Penny," he finished, wondering if she were home, as she didn't always let him finish it.

The door burst open, and Penny flew at him. "I never thought I'd miss that OCD knock of yours Sheldon. Welcome home," she blurted as she embraced his stiff form.

He cautiously allowed his arms to fold awkwardly around her for a few seconds. "Yes, well, thank you. I must say that I am not displeased to see you again, Penny."

She pulled back with a headshake. "Yeah, thanks, Sheldon." Her eyes scanned his face. "Nice beard. You look good with it." She collected her memory. "Very Spock-like," she offered.

He gave her pleased smile. "Thank you, Penny."

She looked behind him. "Where's Leonard?"

"He is currently meeting our new neighbor, Vivienne."

"Oh," Penny said with a worried frown marring her usually sunny face.

"Did you do as I asked, Penny?" At her blank look. "In regards to our apartment?"

"Oh, yeah, Sheldon." She reassured him absently. She hesitated and then asked, "Did you notice anything…weird about Vivienne?"

Sheldon stared at her in puzzlement and then apparently made some kind of connection in his big Sheldon-y brain. "She is not more attractive than you are, and will not be replacing you as the 'Queen Bee' of our social group."

Penny's racing mind stuttered to a halt. "What? No, that's not…what?" She blinked up at him. "Th-thanks, Sweetie, but I'm actually more worried about… here, come in, will ya'?" She grabbed his wrist and gently pulled him into her apartment, unaware of the other guys gaping at them in shock from the top of the stairs.

"I knew I should have gone straight over to Penny's," Leonard said with a whine in his voice.

"Yeah, 'cause it's first come first serve," was Howard's sarcastic rejoinder.

"Man, I just can't catch a break," Leonard said.

Inside Penny's apartment, she offered Sheldon some tea, and once it was made settled beside him on the sofa. "There is something really weird about that Vivienne, Sheldon." She confided to him.

Sheldon stared at her in consternation. "Are you jealous of her?" He asked bluntly.

She sighed. "I thought so at first, to be honest. But, she really acts weird."

"In what way does she act 'weird'?" Sheldon asked after a pause. Penny was far more adept at social mores than Sheldon was, and he was willing to accept that she had noticed something peculiar about the new neighbor.

"It's really hard to put into words, Sheldon. She's old-fashioned, but that's not really that weird. So are you kinda'. But her responses to things I say is…off. I don't how else to explain it. It's almost like she's reading from a script, playing a part."

Sheldon held her eyes. "What precisely do you expect me to do about it?"

"Nothing, really. I just know that you're much smarter than I am, plus you have your Vulcan superpowers. I thought maybe if you were actually paying attention, you might notice what I noticed. Or see whatever it is I'm missing to make her make sense." She shrugged, hoping the combination of truth and flattery would push the balance to her side.

"I see." He stared thoughtfully into the space above Penny's left shoulder for a few moments. "If you are genuinely concerned, and not merely jealous," he said with a stern look at her, "then I will attempt to ascertain if there is anything peculiar about her."

Penny heaved a relieved sigh. "Thank you, Honey. It means a lot to me. I really hope I'm just jealous. Because the alternative is that our new neighbor is a freakin' vampire. And I just don't see how that can be possible."

"Vampire!" Sheldon's voice rose. He stood abruptly. "You think she's a vampire?"

"Silly, right? But Sheldon, I'm completely serious."

He grabbed her hand and pulled her across the hall to his apartment. He ignored the guys lounging on the sofa as he dragged Penny into his room.

"Sheldon?" She asked hesitantly, as he released her and began searching through a binder.

"One moment, please, Penny." He said. He finally found what he'd been looking for, and showed her picture in his binder. "Do you recognize this emblem?"

Penny blinked for a minute, clearly chasing a memory, "Yeah, she has this tattooed on her shoulder. Sheldon, what the hell is it?"

"I believe that you are correct in your assessment. She is a vampire. That emblem is for one of the classic vampire tribes."

Penny's shoulders drooped. She had been hoping that logical Sheldon would tell her that there was no possible way that Vivienne could be a vampire. She had assumed that Sheldon, king of Apocalypse preparation would know about vampires. "So what do we do, Sheldon?"

"We need to collect more data."

"I'm really worried about the guys."

Sheldon looked at her strangely. "The guys?"

"They'll be all over her. What if she eats them?"

Oh," he said. Then "Oh," again when actual comprehension hit him. "We will, of course, warn them."

"They'll never believe she's a vampire, Sheldon. And then we'll lose credibility." She was proud of herself for trotting out that concept.

Sheldon favored her with a searching look. "Indeed. Then we will have to seek confirmation and assistance prior to informing them."

"Assistance?"

"Yes, there is a man who specializes in vampire lore and, if rumor is to be believed, has successfully hunted them. I will contact him after we confirm."

"And just how do you plan to confirm it, Sweetie?"

"We shall have to search her apartment."

"Wow, that's kinda' illegal, Sheldon. Are you sure you want to do that?"

"It's for the greater good. Sacrifices must be made."

Penny was impressed with Sheldon; not only did he believe her, but he was willing to break the law to help her prove it. The smile she gave him was warm, which confused him. They were in the midst of a potentially very serious situation, why was she smiling at him? And with apparent affection. Still, he found himself smiling back at her.

When they walked back into the living room a few minutes later Leonard, Howard and Raj stared at them in surprise. "Hi, guys," Penny said warmly. "Welcome home." Leonard shook himself out of his shock and moved to hug her. She returned it without hesitation. She also hugged Raj, and suffered through an overly-friendly hug from Howard. She sat down and asked about the expedition. Sheldon, who, due to distraction, had remained surprisingly quiet about their findings, immediately started bragging about proving String Theory. It was when he was bragging about the Nobel he was certain to win that Penny caught the expressions on the other guys' faces. Guilty awkwardness mixed with smugness.

"Guys?" She finally prodded.

Penny didn't understand what exactly a can opener had to do with Sheldon's experiment, but she understood the betrayed expression on Sheldon's face.

"Why would you do that?" Sheldon asked in a stunned voice.

"You were being a pain in the ass." Howard replied bluntly.

"So you sabotaged my work?" Sheldon was a genius, but could not comprehend why his ersatz friends would do such a thing.

"Come on Sheldon, no harm done." Leonard sounded like he was talking to a child.

"No harm?" Sheldon's voice went very high and Texas-y.

"Seriously, guys, you screwed up his work?"

"Penny, Penny, Penny, you don't understand science stuff, so just sit there and look pretty." Howard said.

"Well, I may not understand 'science stuff', but you boys clearly don't understand a damn thing about professionalism or friendship. How could you do that?"

"You weren't there, Penny. You have no idea what he was like." Leonard said/whined.

"He was different than he is every day?"

"Well, no, but we were all stuck in that little hut."

She gaped at him for a few long seconds. She was clearly as shocked as Sheldon was and more than a little disappointed. She turned her attention to Sheldon. "Sweetie, I'm going back to my place, do you want to come over for a little while?" She asked gently.

A shell-shocked Sheldon blinked at her for a few seconds, then rose and followed her. He sat in his spot at her apartment. "I can't believe they would do such a thing." Sheldon finally said.

"No, Sweetie, me neither." She raised her hand to pat him in consolation, but stopped herself.

"I thought they …," his voice trailed off.

"I know, Sheldon. I expected better of Leonard, if not the other two."

"He's my best friend." His little-boy-lost sad eyes were making her eyes fill with empathetic tears.

"I know," she said quietly.

They sat quietly for a long time. Penny was hesitant to remind him of their self-appointed task; Vivienne could wait. It was Sheldon himself who brought his focus back to their vampy neighbor.

"We'll wait until after sundown, and scout out Vivienne's apartment, Penny." He said commandingly. It felt good to him to have some control over something, even if was vampire hunting with Penny.

After sundown they watched Vivienne leave the building, and then the two of them cautiously made their way down to the first floor, armed with a couple of tiny video cameras to install in Vivienne's apartment. They knocked on her door, and when no one answered, Sheldon picked the lock (earning a shocked look from Penny), and they eased their way into the apartment.

While Sheldon hid the mini cameras, Penny looked around the apartment. There was no overt evidence that Vivienne was a vampire, but there were no mirrors either, which Penny found suspicious. There was also a banner, with the same emblem that Sheldon had shown her hanging on the wall. Penny took a photo of it with her cell phone.

When they were getting ready to leave the apartment, there was a sound in the hall. Penny leaned against the door, with her ear pressed to the wood, while Sheldon stood behind her, peering out the peep hole. Once they were convinced that the way was clear, they exited and returned to Penny's apartment where they set up the monitoring equipment.

They split their attention between the monitors and the TV, where they watched the "Lord of the Rings" trilogy.

Nothing happened for a long time; they made it through the first movie. Part of the way through the second movie Vivienne's door opened and a man walked in, apparently kissing nothing. Penny and Sheldon looked at the screen, then each other.

"Oh, God," said Penny. "I really wanted to be wrong."

They watched as the man's shirt unbuttoned itself, and his pants followed. Penny and Sheldon shared an uncomfortable look. "You're recording this as evidence, right?" Penny asked.

"Of course."

"Then I don't think we need to watch, do you?"

"No, no I don't." He was happy to agree. He shut off the video, and returned his attention to the television.

The movie ended but neither made a move to get up. Sheldon didn't want to admit that he was a little frightened now that vampirism had been confirmed. Penny was certainly able to protect herself and perhaps him if he stayed close to her. That was not even taking into consideration that he really didn't want to share quarters with Leonard right now. The trick was getting her to ….

"Do you want to sleep here tonight, Sheldon? I know it's not…."

"Yes," he interrupted. He didn't know why she had suggested it, but he certainly didn't want her to change her mind.

She blinked at him in surprise. "Oookay, um, you can sleep on the couch and…."

"Penny, Penny, Penny. You know that won't work. I sleep in a bed. And remember my big Cornish head."

"I had forgotten about that." She hesitated. She really did not want to be alone in her apartment now. She sighed, If it had been any other male of her acquaintance they'd be sharing the bed, but oh, no not Sheldon. She sighed again. "All right, Honey, but no more poetry. Do you want to go get your pajamas, while I make up the sofa?"

"Thank you, Penny." He said meekly.

Sheldon returned to his apartment, where Leonard, Howard and Raj were watching television. He ignored them, an attitude that they returned. Although, when he returned in his pajamas and headed to the door, he had their undivided attention.

"Where ya' going, Sheldon?" Leonard asked.

"Not that the matter is any of your concern, but I'm sleeping at Penny's tonight."

"O-on the sofa?" Leonard squeaked.

"That's insane on the face of it. I'll be sleeping in Penny's bed, of course."

"Again?"

"Again?" Chorused Howard and Raj.

"Yeah, Sheldon got locked out, while we were in Vegas, and stayed at Penny's." Leonard's tone was bordering on hostile.

"Yes, and now if you'll excuse me, Penny is waiting." He spared them a last disdainful look and left.

The guys followed him to the door, and watched Penny let him in after his ritual knock. She was wearing "Hello Kitty" shorts and a tank top. She looked over and saw the guys. She pursed her lips in anger, and closed the door.

"I just can **not** catch a break," Leonard whined.


	2. Chapter 2

A/N Please suspend belief for the mis-matched timelines.

Spoilers for "Fright Night".

Peter Vincent was lying in his large bed, drowsy and content, with a brunette kissing along his chest, when his private line rang. He tried to ignore it, but it was quite insistent. Finally, in frustration he pushed the woman away and grabbed his phone. "What?" He demanded into the phone.

Whoever was on the other end hesitated then spoke, his voice arrogant. "This is Dr. Sheldon Cooper, I live in Pasadena and my neighbor is a vampire."

Peter blinked, "I'm sure you're mistaken."

"I'm quite certain that I am not." The voice was firm. "I am, in fact, sending you photos now. Once you have reviewed them, you will see that I am correct."

Peter hesitated. Last time he had dismissed someone, Charley had nearly lost Amy forever. "I'll look at what you've got. But, I'm making no promises."

"I understand. Good day, Mr. Vincent." And the strange man hung up.

After Sheldon hung up he sat on Penny's bed, staring at his phone for a few minutes. He had spent a restless night in Penny's bed. His over-active brain had turned over the knowledge that his best friend had betrayed him professionally. If he believed in God, which he did not, he'd be thanking said deity for Penny. Her distraction of the day before had been the only thing that kept him from emailing his supposed findings to all and sundry. That would have been one humiliation too many.

He was still at a loss as to why his friends and treasured acquaintance would do such a thing to him. He knew that he did not comprehend social constructs the way that Penny did, but he felt certain that friends just did not do such a thing to one another. Penny's reaction the night before to their confession had seemed to confirm Sheldon's assumptions.

If the only person he could trust was Penny, where did that leave him? He valued his routines, but was uncertain if he could stand to continue with the others in his life after their betrayal. He had managed without them before he'd met Leonard, who'd brought the others, and was certain that he could do so again. Penny might be willing to drive him around in lieu of Leonard; especially after a successful result with the vampire. He had never considered trying to appear well in someone else's eyes. But, circumstances seemed to conspire so that he had to stay in her good graces. Perhaps he could find other ways to be integral to her daily life.

Penny was a kind-hearted person, and unless he angered her beyond redemption, he should be able to maintain her friendship. He might have to listen to her talk about shoes, but it was a sacrifice that he was prepared to make. He sighed.

Penny lay curled up on her sofa. She'd heard Sheldon get up, and make the phone call. Truthfully, she was a little worried about him. She didn't really understand what the guys had done to him, but she got that it was huge; that they had somehow sabotaged him on his drive to win his Nobel Prize. She felt really bad for him and worried about what he might do. As long as there was something going on that could distract him, keep him engaged, she thought that he'd be better off, and not dwell on what the guys had done.

And they didn't even seem to get that they'd done something really bad. Even she got that and she wasn't even a freakin' genius! What the hell did they teach these guys in graduate school? Screw your friends over when they're vulnerable? And to make it worse, they were acting like it was Sheldon's fault, somehow. Like they didn't know what he was like before they left. What the hell was that?

Sheldon had jumped right in to help her when she had come to him with her problem, even before finding out what the guys had done. While she didn't think she could help him, she sure as hell could offer him sanctuary at her place. And maybe find things to keep him distracted.

That decided she got up to face the day. "Hey, Sheldon, I need to get in there, okay?"

"Of course, Penny." He looked at her for a minute. "Thank you for letting me stay here last night."

"Aw, Sweetie, you're welcome anytime. As long as you're not rude to me, anyway."

He gave her a sweet smile. "Agreed, and thank you."

"That's what friends are for. Real friends, anyway," she muttered the last under her breath. But he had no trouble hearing it.

He found her anger on his behalf rather endearing. "I did speak to Peter Vincent," he said at last.

"The Peter Vincent?" At Sheldon's nod, "wow, that's amazing. Is he coming down?"

"He is reviewing the photographic evidence now. I am confident that he will be here shortly thereafter." He paused. "I'm going to complete my ablutions, and then I need to go to work."

She hesitated. "Do you want me to drive you, Honey?"

Blue eyes blinked at her gratefully. "Yes, please. I am hesitant to ride with Leonard, currently."

"I can understand that. I'll be ready in a few."

"Thank you, again, Penny."

"You're welcome, Sheldon."

Sheldon took his shower and was about to shave, when he remembered Penny's comment from the day before. "Nice beard. You look good with it." And she had said that it was "Spock-like." After a brief hesitation, he decided to keep the beard. He supposed that the rugged look was more fitting for a vampire hunter. And if a tiny little part of his brain was pleased that Penny liked it, well that was a secret he would take to the grave, tics or no tics.

In the car Penny offered to pick him up, to give him more of a buffer from Leonard. He happily accepted, aware that her own work schedule would not always allow her to do so.

During the day, the others made no attempt to see him, for which he was grateful. He had no desire to see any of them.

Leonard, Howard and Raj had agreed to give Sheldon a little space to get over the incident at the Arctic. It was no hardship for Howard, as he didn't really like Sheldon most of the time, anyway. He still couldn't believe that he'd allowed Leonard to talk him into schlepping all the way up there, in the first place.

Leonard figured that eventually Sheldon would need something, a ride or something, and come crawling back. He was a little surprised at Penny for taking Sheldon's side. He knew that Sheldon had annoyed *her* often enough. For just a second he considered the possibility that Penny liked Sheldon, as more than friends. But, he dismissed it immediately. He wasn't even sure that Penny liked Sheldon *as* a friend.

Then he had a thought that perked him up. Maybe she was trying to make him jealous, or, and here he grinned. She was jealous that he'd greeted Vivienne before coming upstairs. Yes, he was sure that was it. Penny was punishing him, because she was jealous. He well remembered her behavior when Alicia moved into the building. Well, he would just have to feed that fire.

Sheldon heard from Peter Vincent after his solo lunch. "Don't do anything, my team and I will be there Friday."

"Friday," Sheldon echoed. "But that's 4 days from now."

"I know, but it's the best we can do."

"Very well, Mr. Vincent, I shall see you on Friday."

"Right, then. Bye."

Sheldon stared at his phone in consternation, and then called Penny. "Hello, Penny, Sheldon Cooper here."

A bemused Penny answered. "Hi Sheldon."

"I have just heard from Peter Vincent. His team will be here Friday."

"Friday?"

"I know, but it's the quote best they can do end quote."

"Did you do the air quotes, Sweetie?" She asked with fond amusement in her voice.

"Of course," he answered, puzzled.

"Of course," she repeated. "Well, I guess we'll talk more tonight, when I pick you up."

"That would be acceptable." He paused. "Good day, Penny."

"Goody day, Sheldon," she echoed solemnly.

Penny tidied her apartment, figuring that if Sheldon was going to feel comfortable there, it would need to be a lot cleaner than she usually kept it. She wasn't a slob per se, she just preferred to let things accumulate and deal with it all at once. Sheldon seemed to prefer to deal with things as they came. She wasn't sure there wasn't some kind of a life lesson in there.

As she was changing the sheets, she wondered if he would sleep there again. If Peter Vincent (OhMyGod, The Peter Vincent was coming to her apartment! What a hottie!) wasn't due until Friday, that was 4 days and nights of a vampire running free in the building. Although, Vivienne had been there for most of the summer and hadn't done more than creep her out, so she wasn't sure that she was in immediate danger. Still, she'd kind of convinced herself that she was crazy to think vampire, and was able to sleep. But now she knew it was true. She shivered.

And what about poor Sheldon? He'd probably feel better at his own place. Maybe he'd let her sleep on his couch? It was bigger than hers. Of course, that meant they'd both have to deal with Leonard, and she was still pretty disappointed in him. First, after sniffing around her for months, the first thing he does after a three month absence is "meet" the new neighbor. That was so typically Leonard, cats in boxes and whatever, but, any cute girl and his attention wandered. And secondly, and really most importantly, she was super disappointed in what he'd done to Sheldon. Just, no. Never going to understand that.

She liked Leonard, he was nice and sweet. Well, she'd thought he was, anyway. She was definitely going to have to really rethink that when this was all settled. Sheldon treated her better and he didn't even like her like *that*. Hell, sometimes she wasn't sure he liked her at all. But he was pretty consistent in how he was with her. There was something to be said….What are you thinking? She asked herself. Sheldon didn't have sexual inclinations. Even thinking of him in those terms is a waste of time. Focus. Help Sheldon, who is your friend and deal with the vampire.

That became her mantra over the next few days as they awaited the arrival of Peter Vincent. She picked him up from work, and he immediately fetched his laptop, a few comic books and DVD's and settled himself on her sofa. Sheldon, it appeared, preferred to stay at her place. They watched the "Superman" movies, and he explained the differences to her. She'd honestly had no idea that there was more than one, but Sheldon was surprisingly patient in his explanations.

At some point during the movies, she dozed off, and awoke to a wide-eyed Sheldon staring at her head on his shoulder. "Sorry, Sheldon," she apologized, sitting up straight in embarassement.

For his part, Sheldon was aware that Penny was tactile. He had not realized that this need was subconscious, instinctive. He added it to the list of things he would have to tolerate to keep her friendship. Since she had not mentioned shoes once, he felt that he was still ahead of the game "It is…acceptable." He finally said, confusing her even further.

"It-it is?"

"Of course it is. Offering comfort to one's friends, whether figuratively or literally, is a non optional social convention."

She blinked at him, and her green eyes warmed. "Right as usual, Dr. Cooper."

He smiled, pleased.

After a brief hesitation, Penny returned her head to his shoulder. Sheldon found the warm weight not nearly as discomforting as he expected. His eyes grew heavier and heavier, and his head came to rest atop hers.

Neither mentioned it the next morning, not wanting to upset the fragile balance they were maintaining. On Tuesday, Penny was able to drive Sheldon to work, but not to pick him up as she worked. Leonard, who had mired himself in the delusion that Penny's distance stemmed only from jealousy, approached Sheldon at work.

"Hey, buddy. Need a ride home?" He asked casually, and as if nothing had occurred.

It was on the tip of Sheldon's tongue, metaphorically, of course, to accept, as he did need a ride, but decided that he would rather walk, than let Leonard believe that all was forgiven. "No thank you."

Leonard was surprised. He knew Penny had to work. "Okay, well, see you later then."

"Good day."

Leonard left, wondering which non-Sheldon-approved restaurant they would eat at tonight. He stopped short. Tuesday was Cheesecake Factory. Maybe he should go, anyway. He was certain that Sheldon would cave rather than have his routine upset.

After work, Sheldon walked to the Cheesecake Factory. Someone was at his usual table, but he was early. And, it suddenly occurred to him, he would not be needing a table for four. He looked around at the other tables, and tried to select another that would meet his criteria.

Penny studied him silently as he stood in the entrance and did some kind of formulas in his head. She was a little surprised that he had kept the beard, but had to admit that she liked it. Finally, his head lifted and his eyes sought her out. He found her watching him, a fond smile on her face. He unaccountably blushed. She walked over to him. "Pick one, Sweetie?"

He nodded, "yes, I would like to sit at that one." He pointed to a two person table near his usual one.

"Okay, Sheldon, this way, please." She led him over to the table he had selected. "Your usual drink?" She asked once he was seated.

"Yes, please."

While Penny went to get Sheldon's drink and meal, Leonard came in, looked around in surprise that Sheldon was at a different table, and came over. "Hey, buddy. You weren't going to start without me, were you?" He said boldly.

Sheldon looked at him in shock, unable to formulate a response. Fortunately, he didn't have to. Penny had seen Leonard come in, and seeing Sheldon's distraught expression, prepared a counter-strike. She walked back to Sheldon's new table with a tray. She put Sheldon's food in front of him, and a second meal at the other seat. "Hi, Leonard," she said calmly. "There's not really room for you." Her tone was pleasant.

"What do you mean?" Leonard asked querulously. "What's going on?"

"I'm taking my break, and eating with my friend," Penny replied calmly.

Sheldon looked at Penny in pleased surprise. She had never done this before, but he would much rather eat with her than Leonard. She threw a glance at Sheldon, before returning her attention to Leonard. "Sorry, Leonard, maybe the hostess can find you another table."

Leonard was stunned by the rebuff, before collecting himself. "Well, maybe I'll just go see if Vivienne would like to grab a bite."

Penny froze and exchanged a look with Sheldon. "You don't really know her, Leonard, are you sure that's a good idea?" She finally asked as she sat down across from Sheldon.

"Oh, I'm sure it'll be fine," Leonard said breezily, having noted Penny's displeased expression.

"Really, Leonard, have you forgotten about Alicia?" Sheldon asked.

Leonard shot a smug look at Penny. "No, I haven't forgotten Alicia."

Penny opened her mouth to say something, but clearly thought better of it. "Sheldon, your food is getting cold, Honey." She finally said.

Leonard looked between the two of them before finally leaving them.

Once he was gone, Sheldon met Penny's eyes. "Thank you, Penny. I had not expected him to make such a bold offensive."

She grinned at him. "I really hadn't, either. But I hated to see you eat alone, that's why I…," she trailed off with a gesture at her plate.

Sheldon gave her a sweet smile.

Their meal passed pleasantly, and afterwards, Penny cleared their plates. Sheldon opted to wait until the end of her shift, which was a little over an hour away, so he pulled out his laptop and did some work.

When they walked into the lobby of their building, they heard Leonard's voice coming from Vivienne's apartment. "Are you sure there isn't something I can do for you?" His tone was bordering on whiny.

Sheldon and Penny exchanged a concerned look, before continuing up the stairs.

The rest of the week moved along similar lines, Penny took Sheldon to work every day, and either picked him up if her schedule permitted, or he walked to the Cheesecake Factory to wait. In the evening, Sheldon would bring movies over for them to watch, and they sat together on her small sofa to watch, and Sheldon continued to sleep in her bed.

He found that he didn't really miss having Leonard and the others in his life. His main problem seemed to be retaking his apartment. Leonard had invited Vivienne up to their place, and Sheldon became even more reluctant to sleep there. Really, had Leonard no sense of self-preservation? Inviting a vampire in? He scoffed. He wondered if the invitation to the apartment allowed her access to Sheldon's room. He certainly didn't want to find out by having her steal into his room whilst he slept and bite him. Penny, of course, hadn't invited her over her threshold.

On Friday morning, Sheldon was aware of a strong sense of relief. Peter Vincent and his cohorts would be arriving this evening, and the matter would be settled. Then he would have to deal with Leonard. He and Penny hadn't discussed it, although he was certain that she was on his side. It was reassuring having Penny metaphorically watching his back. She was also easier to share space with than he had expected. She was far more accommodating, and amenable to his movie suggestions.

She dropped him off at work, and arranged to pick him up for their meeting with Peter Vincent.


	3. Chapter 3

A/N Remember: this is fiction.

Penny and Sheldon walked up the stairs towards their apartments. Sheldon spoke, "I'll just grab us a few movies, Penny, and be right over."

"Okay, Honey."

Sheldon put his key in the lock, opened the door and froze. Vivienne was sitting on the sofa, in *his* spot. At his entrance, she looked up with a smug grin on her pretty face. Sheldon, poor as he was at reading expression, had the strong impression that her smugness was not directed at himself, but at Leonard. Leonard was in the kitchen plating some kind of take-out meal.

Sheldon just stood and stared for a few long seconds. It was Howard's voice behind him brought him back to his circumstances. "Hey, Sheldon, move will ya'?"

Sheldon turned sideways to allow Howard and Raj to pass.

When he turned to face the room again, Vivienne was staring at him, her dark eyes mesmerizing. Sheldon blinked.

"I'll be at Penny's, good evening." Sheldon said a little abruptly. Vivienne looked surprised at this.

"Yeah, yeah, goodnight." Howard said, vaguely, before turning his full attention to Vivienne. "Well, hello, Vivenne. May I say that you look lovely this evening?"

"Hey, Sheldon, tell Penny goodnight, for me." Leonard said smugly.

Sheldon closed the door behind him and scurried across to Penny's without a movie selection. He did his ritual knock on her door. Once he finished that she opened the door.

She noticed his empty hands, and raised her eyebrows at him, even as she moved to let him in. As soon he stepped into her apartment, he firmly closed the door behind him. "She's sitting in my spot," he hissed.

"They invited her in?" Penny wanted to be more surprised, but she was just disappointed.

"Leonard has ever been ruled by his penis, rather than his slightly higher than average intellect."

Penny blinked in surprise and then grinned up at him. He gave her a tiny smile in return. "Do you know a way to, what, *un-invite* her?" Penny finally asked.

"I will have to look into the matter. Perhaps Peter Vincent will be able to offer a suggestion when he gets here this evening."

"I sure hope so, Sheldon. I really hate the idea of her having free reign over your apartment, until she gets…dealt with."

"No more than I, Penny."

She stared at him for a few seconds. "Are you hungry, Sheldon? I was going to make some spaghetti, if you want some."

"Do you have hot dogs?" He asked eagerly.

"What?"

As he replied, he moved into her kitchenette. "Mom always cut up hot dogs and put them in the spaghetti sauce…ooh, you even have the same brand of sauce. You're in for a real I-talian treat, Penny." He looked at her with big, hopeful blue eyes, and Penny could no more say no to that look than she could kick a puppy.

"Okay, Sweetie, we'll give it a try."

His eyes lit with happiness at the promised treat, not thinking about the vampire, or Leonard's betrayal. Penny thought it was worth it, even if it tasted awful.

As it turned out, it didn't taste awful. The texture was a little weird, but Sheldon's obvious delight in the meal, made it absolutely worthwhile.

Fortunately for Penny's peace of mind, not to mention Sheldon's good mood they were unaware of the conversation that had taken place in Sheldon's apartment when he left.

"That's your roommate, Leonard? Sheldon, no?" Vivienne asked staring thoughtfully at the closed door.

"Yeah, Sheldon. He's not important." Leonard smiled at her, and with a slow blink, she brought her focus to him. He preened under her attention. "I'm glad you decided to join us for dinner."

"Well, it was hard to turn down your kind invitation, especially after you brought me my mis-delivered mail. Again." There was something in her voice that gave Howard pause, but she leaned forward to pick up her plate from the coffee table in a fine display of cleavage, and he forgot all about everything else.

After dinner, Sheldon fretted about what they should watch. Penny had many "chick flicks", but those had no interest for Sheldon.

He caught her guiltily biting her bottom lip as he perused her DVD selection. His stomach tightened painfully. Had even Penny, the last person he trusted in Pasadena, betrayed him somehow? "I have a confession to make, Sheldon. While you guys were gone, I borrowed 'Iron Man'." She looked at him with sincere green eyes as she rushed to continue. "I know I shouldn't have, but I saw bits and pieces and thought it looked interesting. And I returned it, exactly where you had it, Sheldon, I swear. And then I bought my own copy." She looked at him anxiously, worried about his reaction.

Sheldon felt the tension release itself, and he relaxed. "Ordinarily, you would have courted a strike, Penny, but since this means that we have something acceptable to watch tonight, I will allow it to pass. This once."

Penny felt her shoulders relax. "And I appreciate it, Sheldon."

He gave her a tiny smile in reply, and settled himself on her small sofa, while she fetched the movie from its hiding place and loaded it.

Suddenly, he realized what had actually happened. Penny *bought* "Iron Man". He felt a smirk pull at his mouth. "What?" She asked nervously, as she took her seat next to him.

"You bought 'Iron Man'," he replied his smirk in no way abated.

Penny stared in bemusement at his smirk, thinking that it suited him, especially with the sexy beard, when she got the point he was making. "I know, I know, 'one of you, one of you', but, seriously, it's a good movie, Sheldon."

"I concur." And he turned his attention to the credits that were starting up. She was sitting close to him, her arm barely brushing his as they watched the movie together.

The movie had only been over for a few minutes when there was a knock at the door. Penny and Sheldon exchanged a look, and rose as one. Penny peeped out and saw Peter Vincent looking impatient.

She opened the door, and stepped back to stand next to Sheldon, not inviting in him, but allowing him to enter. He gave her an approving nod for her caution and stepped in, warily looking around.

"Peter Vincent," he offered.

"Dr. Sheldon Cooper," Sheldon responded coolly. "And this is my …friend, Penny."

"My friends, Amy and Charley." He gave Sheldon a considering look, and really looked at Penny. "Well, hello, there." He said.

Penny blinked, moved marginally closer to Sheldon, and took his hand. Penny wasn't shy of men, and had no problem flirting, but, some men were not safe to flirt with, and Peter Vincent, gorgeous as he was, definitely fell into that category, with his naughty smirk and wicked eyes. Sheldon froze at her side, then seemed to actually grasp that Penny was seeking *his* protection, although from what he wasn't clear. He allowed her lace their fingers together, and gave a reassuring squeeze. Penny sagged a little in relief and then chastised herself. Sheldon had never let her down.

Peter heaved a huge, mostly insincere sigh. "How do you skinny geeks keep getting the hot blondes, heh?"

Charley's answer was a little surprising to Sheldon and Penny; less so to Amy and Peter. "Maybe, because, we let them know who we really are. And somehow, they like us anyway." He shot Amy a fatuous look. She returned it in full measure.

Sheldon spared a second to ponder that as he studied Penny, gave a tiny nod to himself, and turned to Peter. "Be that as it may, the real issue is the vampire."

"Okay, true enough." Peter allowed. "What have you got?"

Penny allowed Sheldon to make the explanation and show the evidence that they had gathered. Peter flitted around Penny's apartment while Sheldon spoke, whereas Charley and Amy paid close attention.

"What kind of kill total has she got?" Charley asked bluntly, once they'd gone through the evidence.

Sheldon looked blankly at him. "What do you mean?" Penny asked for them both.

"You know, disappearances, bloody corpses turning up?" Charley explained patiently.

Penny and Sheldon exchanged a look. "It never occurred to me to look," Sheldon admitted.

"It probably doesn't matter, but…." Charley trailed off.

"It's worth checking out, regardless." Sheldon agreed. He pulled is laptop off of Penny's coffee table, and began to quickly search. Penny looked around, suddenly realizing that she had lost sight of Peter Vincent.

Amy spoke up, "He's probably poking around your underwear drawer."

"Oi!" Peter's voice protested from the bedroom.

Penny rushed to the bedroom door and froze. Peter Vincent had removed his black leather jacket and was sprawled on her bed in his black t-shirt and jeans. He threw an inviting smile at her. For one crazy second, Penny was tempted by the promise in his dark eyes. But he might as well have had a flashing neon sign above his head that said "Not Safe." Penny decided to leave Peter alone and retreated to sit on the arm of the sofa next to Sheldon. Sheldon glanced up from his laptop, gave her a concerned - for him- look. She smiled reassuringly at him, and he returned his attention to his research.

They were unable to find any deaths that they could attribute to Vivienne, which could mean that she was hunting outside the expected zone; which was entirely possible. But it gave Penny just the tiniest doubt. "What if she isn't…?"

"Penny, Penny, Penny, all of the evidence points to her being a member of the undead."

"I know, Honey, but…."

"If she's a vampire, which seems likely," Amy spoke, "she has to be getting blood somewhere. They have literally no choice." Amy sounded so certain that Penny gave her a peculiar look. "I was turned, Charley and Peter saved me."

"Oh," Penny said. She thought that it was probably inadequate, "I'm glad they were able to save you." She offered finally.

Amy gave her an understanding smile. "Thanks."

"Pete?" Charley called. "How do you want to handle this?"

Peter appeared at the bedroom door, hair mussed, and with a small smirk on his face. "I think we need to take a look around her lair, first. We can plan better from there."

Penny nudged Sheldon, who looked blankly at her. "The video equipment, Sweetie. So we know when she goes out."

Sheldon's expression cleared with comprehension, and he pulled up the monitoring information. The five of them huddled around the monitor. Well, four of them. Peter wandered aimlessly through the apartment, opening cabinets, peering curiously into drawers, shaking the bottles of liquor and just generally being nosy.

Twenty-something minutes later, Vivienne left the apartment. Or rather, her door opened and closed and they assumed that she left. A minute or so after that, they heard her coming up the stairs. Penny, peeking out the peephole, saw her pause, cast a look at Penny's door, and then knock on Sheldon's door. Leonard opened the door, and allowed her in, throwing a triumphant smile at Penny's door before closing his.

Penny turned to the others. "She's across the hall," she reported. They looked at each other for a second, and Penny continued. "I think Sheldon and I should go and make sure she stays put, while you guys check out her place."

Sheldon balked. "Surely…," he started.

"Sheldon, I need you." Penny said simply.

Sheldon took a deep breath, squared his shoulders and nodded. "Very well," he agreed.

They exited the apartment and crossed the hall. Sheldon hesitated, felt Penny's reassuring warmth at his side and then opened the door. Only to freeze at the sight of Vivienne once more in his spot. Penny knew that she should let it be, let Vivienne have the spot, but Sheldon was being so amazing that she just couldn't let it go.

"I'm sorry, but you're in Sheldon's spot. Could you move over please?"

"He can't sit somewhere else?" Vivienne questioned, amusement in her voice.

"No," Penny said firmly. "That's his seat. You see in the winter that seat is close enough to the radiator so that he's warm, yet not so close that he sweats, in the summer it's directly in the path of a cross breeze created by opening windows there," gesture to window, "and there," gesture to other window, "and it faces the television at an angle that isn't direct so he can still talk to everybody yet not so wide that the picture looks distorted." Penny finished.

Leonard was gaping at her, suddenly less certain that Penny had no romantic interest in Sheldon than he had been. For his part, Sheldon bent a look of stunned approval upon Penny. Penny held Vivienne's eyes until finally Vivienne shifted smoothly over two places on the sofa.

Sheldon settled himself happily into his spot. He had missed his spot. Penny sat on the middle cushion, between Sheldon and Vivienne. Sheldon spared a glance at Penny and then deliberately allowed his arm to rest against hers.

Meanwhile, down in Vivienne's apartment, Peter was going through every shelf, drawer, nook and cranny of the apartment. Anything he deemed significant, he had Charley photograph. Amy, with her unique perspective, was getting a feel for the apartment. She found them in the closest in the large bedroom.

Howard and Raj were just standing there, looking blank. Amy let out a gasp and jumped back. The two men stepped out of the closest towards her, and she rushed into the other room. "She's enthralled two guys, Penny and Sheldon are in danger," she burst out as soon as she entered the room. Peter and Charley exchanged a quick look and made for the door, Amy right behind them.

They ran up the stairs, and burst into Sheldon's apartment without any ado. Vivienne was now sitting on the arm of the chair where Leonard was sitting. When the others burst into the room, Vivienne took one look at Peter, hissed and drew her nail across her breast drawing blood. She pulled Leonard's head towards her breast. Leonard took one look at her lush bosom, blinked at the blood and promptly fainted.


	4. Chapter 4

Vivienne watched Leonard fall to the floor with disbelieving eyes. "Really?" She asked his prone form.

Penny couldn't stifle her little giggle. "It's the blood," Sheldon offered from his place beside Penny.

Peter raised his weapon, and pressed the trigger. Nothing happened. "Fucking eBay," Peter snarled. They heard Howard and Raj coming up the stairs. Sheldon darted to his room. Penny stood and stared wide-eyed after him.

Vivienne grinned like a shark and took a step towards Penny. "You started all this, didn't you?"

"This is in no way Penny's fault. Step back from her," Sheldon's voice said firmly from the hallway. They all turned to face him, to see him holding a crossbow on Vivienne.

"Got wood, Sheldon?" Vivienne asked, indicating his arrows.

Sheldon hesitated, and Penny hauled off and punched Vivienne. The next couple of minutes were chaotic, but ended with Penny straddling Vivienne, a stake, grabbed from Charley, poised above her heart. Vivienne suddenly had a lot more teeth, but inexplicably hesitated to attack Penny.

Penny, noticing the hesitation, hesitated in turn. "Where do you get your blood?" Penny asked suddenly.

Vivienne's teeth went back to normal. "I have a friend who works in a hospital, he gets me…." She trailed off.

"Can you release the boys?"

"They'll be released when you stake me," Vivienne said sullenly.

"Is that the only way they can be released?"

"No," Vivienne said with sudden hope.

"Penny," Sheldon said urgently.

"I know, Sweetie, but, what if she's not eating people? Is it right to…?" She gestured with the stake.

"Your contention being that she may be a monster without being monstrous?"

"Peter, is it possible?" Penny looked to the door, where Peter stood nonchalantly leaning against the wall, clearly enjoying the two attractive women scrapping.

"I've certainly never heard of any such creature, but, there are more things in heaven and Earth…." He finished with a shrug. "The question is, love, are you prepared to risk it?"

"Is there a way to un-invite her from Sheldon's place?" Penny countered as moved the stake away from the vampire beneath her. Vivienne remained passive, hopeful for the first time in a hundred years.

"Yeah," Peter said. "There's a way."

"You don't eat humans?" Penny asked Vivienne to be certain.

"Why is Penny sitting on Vivienne?" Leonard asked as he sat up. "Are they fighting?" The "over me," was implied by his smug grin.

"No, I don't, Penny. Not for a long time. Too much blood already." Vivienne's voice was raw. The same instinct that told Penny that Vivienne had been acting a part earlier, told her that Vivienne was being honest now. Penny had no trouble believing her.

"And you'll release the boys?"

"Yes," Vivienne replied.

Penny stood up and offered a hand up. Vivienne raised her eyebrows in surprise as she accepted it.

"Why?" Vivienne asked finally.

"Why didn't you attack me?" Penny returned.

"Someone wanna' catch me up here?" Leonard asked querulously. He was ignored.

"I've seen so much bloodshed already, I just…." She gave an eloquent shrug.

"I wouldn't have thought you could resist." Amy said, with an odd note in her voice.

Charley, clearly remembering that Amy had attempted to bite him, gave her hand a reassuring squeeze.

"A hundred years ago, no I couldn't have. But the older I got, the easier it got to ignore the need for…. I still need blood, but I don't have to hunt for it. Not anymore."

"Oh."

Leonard had been ignored long enough. "Okay, what the hell is going on here. Blood? And what's up with Howard and Raj?"

"Really, Leonard, I would have thought it would be evident to even someone of your intelligence." Sheldon started. Penny glanced fondly at him, and he caught her gaze, and felt the heat rise in his cheeks. "Vivienne is a vampire, and has enthralled Wolowitz and Koothrappali. Peter Vincent and his merry band of vampire hunters came to help us destroy said vampire, but Penny has realized that it is unnecessary. And now Vivienne is going to release Wolowitz and Koothrappali."

"What?" Was all that Leonard could manage.

Sheldon sighed, turned to Penny with a look that said: "do you see the lesser minds that I am forced to deal with?" Penny grinned at him.

"Vivienne, would you please?" Penny gestured at the boys.

"Oh, of course." Vivienne looked into each Raj's eyes and released him, and then did the same for Howard.

Both men blinked rapidly, and looked around them in confusion. "What's…hey, I think there's something wrong with…arg!" Howard broke off as he caught sight of Sheldon's crossbow. "Has he finally snapped?"

Peter actually was the one to answer. "If what I've seen thus far is any indication, he's the only one of you who hasn't."

Howard looked at him in surprise. "You're Peter Vincent."

"I was aware of that, thanks."

"Hey, man, no need to be…."

Penny cut him off. "Peter came to help, what do you remember?"

"Going to Vivienne's apartment and… oh my God." Howard turned bug eyes towards Vivienne. "You're a vampire!"

Taking a page from Peter's book, she replied, "I was aware of that, thanks."

"Sheldon, shoot her!" Howard cried.

"I'll do no such thing. She released you in good faith. Penny, who has a much better grasp of these things, has accepted her word that she does not hunt."

"And you're going to trust a vampire?" Leonard demanded in a whiny voice.

"No," Sheldon said firmly. "I trust Penny." There was something in Sheldon's voice that silenced Leonard.

Howard turned hopefully to Peter. "Can you use that thing?" He pointed to his stake-gun.

"Nah, jammed."

Howard stood there jabbering for a few seconds and looking wildly around the room. Raj slapped him across the face. "Dude, calm down."

"Sheldon hates us now, why would you think that we're safe?" Howard asked harshly.

"Because Sheldon isn't like that," Penny said. "Isn't like you guys. It would never occur to him to do such a thing."

"You think we'd let …?" Leonard trailed off in shock.

"I think you're capable of a lot worse things than I ever would have believed three months ago." Penny replied bluntly.

"What are you talking about?" Vivienne asked curiously.

"They were on an expedition…," Penny started.

"Oh, to the Arctic, no?" At Penny's nod, Vivienne continued. "And something unfortunate happened?"

"Yeah, Sheldon was a ginormous dick." Howard said.

"And these guys screwed up the test results." Penny finished.

"Doesn't it make you all look bad to have false results on a project?" Charley asked, shocked.

"Meh, it was Sheldon's project." Howard said.

"Why did you two save these arseholes?" Peter asked.

"Because it was the right thing to do." Penny said for both of them. Sheldon merely nodded. He'd actually managed not to think about the betrayal for a few days.

"You're a better man than I am, mate." Peter said.

"We like you, anyway, Pete," Charley said with a grin and Amy nudged Pete's shoulder with her own.

Peter smirked at them and draped an arm over each of their shoulders. "Are we ready to un-invite Vivienne from the apartment?"

"Can I ask you something first?" Penny asked Vivienne.

"May you," Sheldon murmured.

"May I?" Penny corrected after rolling her eyes at Sheldon.

"Of course," Vivienne answered.

"How do you look so cute when you can't see yourself in a mirror?"

"I'm one hundred and twenty-four years old. I'm quite familiar with where things are on my face." She smiled as she said it.

"Oh, like Sheldon's imaginary whiteboard."

"Very good, Penny. There may be hope for you yet," Sheldon teased.

She narrowed her eyes at him, and he took a step back, before she smiled at him.

"Hey, Peter?"

Pete nodded at Penny in acknowledgement.

"How come her clothes don't show up either?"

"Ah, that's actually very interesting," Peter, who had made a study of vampires, said. He then went into a long a complicated explanation, made harder to comprehend due to his thickening accent as he got into his explanation.

When he finished, Penny turned blank eyes to Sheldon, who said, "Proximity."

"Oh," Penny said in comprehension. She turned to Pete. "Thanks," with a sunny smile.

"You're welcome?" Pete replied. He said to Vivienne, "I'm ready to do the un-invite. You want to step out?" And he commenced digging into his bag.

The un-invite was relatively easy, and took about fifteen minutes to complete. Afterwards they all trooped down the stairs, where Vivienne was waiting to say good-bye.

Penny stood next to Sheldon, their arms brushing gently. Vivienne stood a few feet away from Penny, and Leonard, Raj and Howard stood on the other side of the Vegas contingent, as far from Vivienne as they could.

"Thank you," Penny said. She hugged each of the vampire hunters. "Really, thank you for coming. Please come and visit any time you're near. We'd love to see you all again."

"We're glad that slayage was unnecessary." Pete nodded at Vivienne.

"Me, too," Vivienne echoed, with a smile. "Goodbye."

Peter looked around, rested a hand on the shoulder of Charley and Amy, and said, "I think it's time we headed on home, kids."

With a last wave, they left. Penny and Sheldon turned to go back upstairs, but Penny stopped abruptly. "The cameras."

"Of course," Sheldon agreed. He turned to Vivienne. "May I enter your apartment to remove the cameras that we placed?"

"Cameras!" Vivienne exclaimed.

"Yes." He answered briefly and then stared at her awaiting a response to his question.

"By all means, please remove them." She gestured towards her apartment. Sheldon hesitated before crossing the threshold and then felt Penny at his side. She gave his hand a quick squeeze, before releasing it. She stood on the doorstep, between Sheldon and Vivienne.

Penny awkwardly bit her lip, "I couldn't help noticing, Vivienne, you have the cutest pair of Louboutins."

"The blue ones?" Vivienne returned with a smile, choosing to ignore that Penny had clearly seen them while snooping through her apartment.

"Yeah," Penny agreed eagerly. "Where did you find them?"

The women spent the few minutes that it took Sheldon to remove the cameras, talking about shoes. They trailed off when he returned to the hall.

"I'm not sure that thanks are appropriate, but, thank you," Vivienne said, finally.

"You should be thanking us," Leonard blustered, clearly feeling that he had been ignored long enough. "You were going to…."

"I was trying to lay low, you were the one who kept coming back, and stealing my mail," she said with a shudder.

Sheldon and Penny exchanged a look.

"I-It was mis-delivered."

"That happens a lot around her," Penny offered. "Ignore it."

"It will certainly cease when Leonard moves out of my apartment." Sheldon said.

"When I what…?" Leonard sounded shocked.

"You imagined that I would permit you to stay after you betrayed me, science and our friendship? As little as I think of your intelligence, I thought you smarter than that."

"Bu-but, we're friends." Leonard protested. He never would have thought Sheldon could forgo his routine.

"I am reliably informed that we are not; that friends do not under any circumstances do what the three of you did. And whilst I will not be pursuing this matter through Caltech, merely reporting the expedition a failure," Sheldon's lip curled as if the very word was distasteful to him, "I will not be content with you in my personal life. I would not know what betrayal might next come."

"You want to talk about betrayal?" Leonard said hotly. "What about you and Penny, huh? She was mine."

"Yours?" Penny said in surprise.

"Uh, oh," Howard said. Raj, having gotten over his shock and remembering that he couldn't talk in front of women, merely nodded.

"Well, yeah, kinda'. I saw you first and talked to you. I had dibs."

Penny's face was a mask of rage. "Dibs? Who the hell do you think you are?" She stepped towards Leonard, mayhem written all over her frame. "You obnoxious, whiny, little prick…." She would have continued in this vein, had she not caught sight of the anxiety on Sheldon's face. She raised her eyebrows in question.

"Please don't fight, Penny." He said in a small voice.

Penny deflated, shot Leonard a venomous look and said, "I'm sorry, Sweetie. He's not worth it anyway. Let's go back upstairs, and watch a movie while Leonard packs, okay?"

Sheldon smiled sweetly at her. "Thank you, Penny." And followed obediently after her. Once upstairs, Sheldon grabbed a couple of movies he thought Penny might like, based on her interest in "Iron Man", Peter's faulty stake-gun, which he'd left on the floor and returned to Penny.

Downstairs, the other three guys stood and stared at each other, then turned as one to look at Vivienne. "Don't look at me; I don't want to have anything to do with you, either." And she went into her apartment and firmly closed the door. They heard the lock click into place.

It actually took Leonard all weekend to get all of his things out of the apartment, and Sheldon spent that time at Penny's. Turns out she really liked "Thor" and thought Loki was awesome (she didn't mention that he reminded her of Sheldon).

Leonard ended up having to store most of his stuff, and stay on Howard's couch. They couldn't really hang out at Howard's, because his Mom was really loud. They tried to hang out at Raj's, but it was kind of small.

Sheldon was dreading having to look for another roommate, when it occurred to him that he and Penny had cohabitated quite well. He worked at his board feverishly, trying to work out mathematically whether he and Penny could coexist. In the end, it was the realization that he wouldn't really trust anyone else in his space that made him suggest it to her.

Penny considered long and hard, tried to be logical and weigh the pros and cons, and finally decided that it was a practical and logical solution to her always-present financial woes as well as persistent loneliness that drove her to sometimes bring men home.

They trundled along happily, Sheldon getting increasingly more willing to be touched, and occasionally touching her if the situation warranted it. As the months went slowly by, fall sliding into winter, Penny got a few acting gigs, which made her happy.

Sheldon had taken apart Peter's stake-gun, reassembled it better and mailed it back to Peter. Peter was quite pleased with how well it worked, and asked Sheldon if he could send him something else he'd bought that didn't work properly. Sheldon agreed to look at the item. They went back and forth with weaponry in this fashion, Sheldon honestly dismayed at how much stuff Peter bought that didn't work as it should.

Penny and Vivienne hung out sometimes, at Vivienne's place, and often went clubbing together. Vivienne had to be careful, because her reflection didn't show up, but Penny was a surprisingly quick-witted ally. They also shoe shopped, online, as Vivienne had found some really awesome bargain sites. Sheldon, in the privacy of his own mind, heaved a sigh of relief that he would not be expected to listen to Penny talk of shoes.

On their way out to a club one evening, the two women ran into Leonard coming to pick up something he'd "accidentally" forgotten. He froze at the sight of Vivienne, and then looked confused as to what she and Penny would be doing together.

Neither woman acknowledged him, but being Leonard, he forced the issue. "Where are you two headed," he asked.

"Not that it's any of your business, but to a club," Penny answered.

"Are you sure it's safe, Penny?" He asked with a nervous look at Vivienne.

"I'm sure I'm safe." She barely emphasized the second "I'm".

Leonard turned to Vivienne, "you'd better not hurt her." He tried to sound threatening.

In a blur Vivienne was in his face with all of her teeth bared. Leonard yelped and tried to step back. With a huff of laughter, she glanced down at his crotch; he had wet himself.

"My hero," Penny said. Leonard didn't need a sarcasm sign to know she didn't mean it. The two women went on their way without a backward glance.

Leonard tried to wheedle his way back into Sheldon's good graces (and more importantly into the comfy apartment), trying to convince him that Howard had been the ringleader. Sheldon was singularly unimpressed with this, and dismissed him.

Howard had bragged about the "prank" the guys pulled on Sheldon, although only the three of them seemed to find it funny. Nothing was ever officially said, so they blithely thought they were free and clear. Until the bill showed up for the fraudulent experiment. All charges from the Arctic expedition, including Sheldon's salary, were being billed to Leonard, Howard and Raj by the NSF. Leonard took it to Dr. Seibert, who looked over his glasses at him, and asked him what he had expected.

Tails between their legs, the guys set up payment arrangements.

More time passed and Sheldon became less and less satisfied with Caltech. On a dreary winter day, Sheldon's phone rang. "Hey, there mate." Peter's voice was cheerful. "How would you and the lovely Penny like to come to Vegas for a visit? We've got a situation and really could use your help."

A/N "…may be a monster without being monstrous" Borrowed with generous permission from ConeycatJr


End file.
